Magnetic substance holding device

Abstract

A magnetic substance holding device includes: a first pole piece assembly including a first N-pole piece, a first S-pole piece, and a first permanent magnet; a second pole piece assembly including a second N-pole piece, a second S-pole piece, and a second permanent magnet; at least one first coil; at least one second coil; and a control device controlling current applied to the first coil and the second coil so as to control magnetic fluxes passing through the first coil and the second coil, thereby allowing the first pole piece assembly and the second pole piece assembly to switch between the first arrangement and the second arrangement, to control magnetic fluxes passing through the holding faces of the first pole piece assembly and the second pole piece assembly.

What is claimed is: 
     
       1. A magnetic substance holding device, comprising:
 a first pole piece assembly comprising a first N-pole piece having a holding face and a contact face and being a magnetic substance, a first S-pole piece having a holding face and a contact face and being a magnetic substance, and a first permanent magnet having an N-pole to be in contact with the first N-pole piece and an S-pole to be in contact with the first S-pole piece; 
 a second pole piece assembly comprising a second N-pole piece having a holding face and a contact face and being a magnetic substance, a second S-pole piece having a holding face and a contact face and being a magnetic substance, and a second permanent magnet having an N-pole to be in contact with the second N-pole piece and an S-pole to be in contact with the second S-pole piece, wherein the contact face of the second S-pole piece faces the contact face of the first N-pole piece, and the contact face of the second N-pole piece faces the contact face of the first S-pole piece; 
 at least one coil wound around at least one of the first N-pole piece, the first S-pole piece, the second N-pole piece and the second S-pole piece; and 
 a control device controlling current applied to the at least one coil, 
 wherein at least one of the first pole piece assembly and the second pole piece assembly is configured to be movable so that a first arrangement in which the contact face of the first N-pole piece is separated from the contact face of the second S-pole piece and the contact face of the first S-pole piece is separated from the contact face of the second N-pole piece, and a second arrangement in which the contact face of the first N-pole piece is in contact with the contact face of the second S-pole piece and the contact face of the first S-pole piece is in contact with the contact face of the second N-pole piece, are switched between each other, and 
 wherein the control device adjusts current applied to the at least one coil so as to control magnetic fluxes passing through the at least one coil, thereby allowing the first pole piece assembly and the second pole piece assembly to switch between the first arrangement and the second arrangement, to control magnetic fluxes passing through the holding faces of the first pole piece assembly and the second pole piece assembly. 
 
     
     
       2. The device according to  claim 1 , further comprising:
 a first connection pole piece having a holding face and a contact face and being a magnetic substance; and 
 a second connection pole piece having a holding face and a contact face and being a magnetic substance, 
 wherein the contact face of the first connection pole piece faces the holding face of the first N-pole piece, and the contact face of the second connection pole piece faces the holding face of the first S-pole piece, 
 wherein the first connection pole piece, the second connection pole piece and the second pole piece assembly are stationary whereas the first pole piece assembly is movable between the first/second connection pole pieces and the second pole piece assembly, 
 wherein the first connection pole piece and the second connection pole piece are arranged such that when the first pole piece assembly and the second pole piece assembly are in the first arrangement, the holding faces of the first pole piece assembly are in contact with the respective contact faces of the first connection pole piece and the second connection pole piece, and when the first pole piece assembly and the second pole piece assembly are in the second arrangement, the holding faces of the first pole piece assembly are separated from the respective contact faces of the first connection pole piece and the second connection pole piece, and 
 wherein when the first pole piece assembly and the second pole piece assembly are in the first arrangement, magnetic workpieces are held on the holding faces of the second pole piece assembly and on the holding faces of the first connection pole piece and the second connection pole piece, respectively, and when the first pole piece assembly and the second pole piece assembly are in the second arrangement, magnetic workpieces are detached from the holding faces of the second pole piece assembly and from the holding faces of the first connection pole piece and the second connection pole piece, respectively. 
 
     
     
       3. The device according to  claim 1 , further comprising:
 a third pole piece assembly comprising a third N-pole piece having a holding face and a contact face and being a magnetic substance, a third S-pole piece having a holding face and a contact face and being a magnetic substance; and a third permanent magnet having an N-pole to be in contact with the third N-pole piece and an S-pole to be in contact with the third S-pole piece, wherein the contact face of the third S-pole piece is arranged to face the holding face of the first N-pole piece, and the contact face of the third N-pole piece is arranged to face the holding face of the first S-pole piece, 
 wherein the second pole piece assembly and the third pole piece assembly are stationary whereas the first pole piece assembly is movable between the second pole piece assembly and the third pole piece assembly, 
 wherein the third pole piece assembly is arranged such that when the first pole piece assembly and the second pole piece assembly are in the first arrangement, the holding faces of the N pole piece of the first pole piece assembly are in contact with the respective contact faces of the third pole piece assembly, and when the first pole piece assembly and the second pole piece assembly are in the second arrangement, the holding faces of the first pole piece assembly are separated from the respective contact faces of the third pole piece assembly, and 
 wherein when the first pole piece assembly and the second pole piece assembly are in the first arrangement, a magnetic workpiece is held on the holding faces of the second pole piece assembly whereas a magnetic workpiece is detached from the holding faces of the third pole piece assembly, and when the first pole piece assembly and the second pole piece assembly are in the second arrangement, a magnetic workpiece is detached from the holding faces of the second pole piece assembly whereas a magnetic workpiece is held on the holding faces of the third pole piece assembly.